Drug resistance is the single greatest reason for lack of HIV control. Quantitative measurements of viral load and drug resistance can provide the information necessary to rationally modify drug therapy. Increasing viral load can be caused by changes in the immunologic status of the patient or the virulence of the virus or by lack of patient compliance with the difficult drug scheduling. Treating patients who may have been infected with a drug resistant virus with combination drug therapy may be detrimental to the patient. Knowing the precise nature of a drug resistant mutation can also be used to predict cross-resistance or reduced resistance to other drugs. This work will develop RT-PCR conditions, primers, capture sequences, and internal standards that make quantitative detection of wild-type and drug-resistant HIV a simple and rapid process, even while accommodating the known sequence polymorphism found in the virus. In this Phase II study, the developed detection assay for the common reverse transcriptase inhibitors (AZT, ddI, ddC, and 3TC) will be expanded to include the protease inhibitors (indinavir, ritonavir, saquinavir, and nelfinavir) and evaluated using clinical samples. The results from this assay will be compared with the more costly DNA sequencing methods and a competing oligonucleotide ligation assay. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE